Appendix M to Part 110—Categorization of Nuclear Material

[From IAEA INFCIRC/225/Revision 5]

Material	Form	Category I	Category II	Category III3
1. Plutonium1	Unirradiated2	2 kg or more	Less than 2 kg but more than 500 g.	500 g or less but more than 15 g.
2. Uranium-235     (235U).	Unirradiated:2
	—Uranium enriched to 20 percent 235U or more.	5 kg or more	Less than 5 kg but more than 1 kg.	1 kg or less but more than 15 g.
	—Uranium enriched to 10 percent 235U but less than 20 percent 235U.		10 kg or more	Less than 10 kg but more than 1 kg.
	—Uranium enriched above natural, but less than 10 percent 235U.			10 kg or more.
3. Uranium-233     (233U).	Unirradiated2	2 kg or more	Less than 2 kg but more than 500 g.	500 g or less but more than 15 g.
4. Irradiated Fuel (The categorization of irradiated fuel in the table is based on international transport considerations. The State may assign a different category for domestic use, storage and transport taking all relevant factors into account).			Depleted or natural uranium, thorium or low enriched fuel (less than 10 percent fissile content)4 5

¹ All plutonium except that with isotopic concentration exceeding 80 percent in plutonium-238.

² Material not irradiated in a reactor or material irradiated in a reactor but with a radiation level equal to or less than 1 Gy/h (100 rad/h) at 1 m unshielded.

³ Quantities not falling in Category III and natural uranium, depleted uranium and thorium should be protected at least in accordance with prudent management practice.

⁴ Although this level of protection is recommended, it would be open to States, upon evaluation of the specific circumstances, to assign a different category of physical protection.

⁵ Other fuel which by virtue of its original fissile material content is classified as Category I or II before irradiation may be reduced one category level while the radiation level from the fuel exceeds 1 Gy/h (100 rad/h) at one meter unshielded.

(Sec. 161, as amended, Pub. L. 83–703, 68 Stat. 948 (42 U.S.C. 2201); sec. 201, as amended, Pub. L. 93–438, 88 Stat. 1243 (42 U.S.C. 5841))

[43 FR 21641, May 19, 1978. Redesignated and amended at 49 FR 47204, Dec. 3, 1984. Further redesignated at 55 FR 30450, July 26, 1990; 58 FR 13005, Mar. 9, 1993; 61 FR 35603, July 8, 1996; 79 FR 39299, Jul. 10, 2014]